Originally Published EMDM November 2005
TECHNOLOGY NEWS
Polymer Provides an Audible Difference
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| An interconnect device used in the Acuris P hearing aid is moulded from a liquid-crystal polymer. The material allows complex fine-line circuit patterns to be laser etched and plated. |
A liquid-crystal polymer (LCP) plays a key role in the fabrication of a hearing aid that reduces background noise while amplifying speech. Supplied by Ticona Technical Polymers (Kelsterbach, Germany), the LCP was modified for use in the Acuris P hearing aid developed by Siemens Medical Solutions.
The Vectra E820i LCP was fashioned into a thin-walled moulded interconnect device (MID) by means of laser direct structuring. This process entails injection moulding the LCP part, drawing a conductor track layout on the surface with a computer-controlled laser, and then electroplating metal onto the track pattern to create a 3-D circuit board on the part’s surface.
“This process allows for fine conductor patterns in almost any layout,” says Jörg Schottek, head of Ticona’s European Vectra business. Because it permits a better use of available space, the process aids miniaturization, he adds. Laser direct structuring is available from LPKF Laser & Electronics AG (Garbsen, Germany).
Hearing aids, like many other medical devices, are squeezing more capabilities into ever-smaller packages. The MID that is part of the Acuris P product measures 3 mm wide by 25 mm long and is part of a system that connects the microphone module to other electronic components.
Copyright ©2005 European Medical Device Manufacturer
